The first way to look at population is as a pure numbers game. More people means more consumers and more emitters, so the thing to do is slow the rise of population. Specifically, since most of the new people are going to come from poor or developing countries, the question is specifically how to slow population growth there.

Luckily, we know the answer. It is family planning that enables women to have only children they want and choose, and education of girls, giving them access to income opportunities outside the home. We know that women, given the resources and the choice, will opt for smaller families.

Those are the two most powerful levers to bend the population curve. They are also, in and of themselves, an enormously powerful climate policy. When Paul Hawken and his team investigated and ranked carbon-reduction solutions for their Drawdown project, they found that the combination of the two (call it the female-empowerment package) carried the most potential to reduce greenhouse gases later this century, out of any solution. (Together they could prevent 120 gigatons of GHGs by 2050 — more than on- and offshore wind combined.)

So if you are concerned about the growth in population, make yourself a champion of female empowerment in the developing world. You will be contributing to the most effective solution to the problem without any of the moral baggage.

And next time you’re at an environmental event, maybe instead of asking the population question, ask the female empowerment question. Why aren’t climate hawks talking about it more? They should be!

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One way to prevent the creation of new high-consumers would be to persuade the wealthy to have fewer babies and to close off the borders of wealthy countries, preventing low-consumers from immigrating and becoming high-consumers. You could try, in short, to engineer population decline in wealthy countries.

That seems … fraught.

For one thing, fertility tends to decline with wealth anyway. For another, any targeted attempt to engineer population decline is going to run into an unholy thicket of moral and political resistance.

Another way to approach the problem would be, rather than prevent the birth of extremely wealthy people, prevent the creation of extremely wealthy people. In other words, prevent the accumulation of massive wealth. You could do that by, for instance, taxing the shit out of wealthy people.

If you approached the problem that way, under the banner of reducing global income inequality, you would find many allies. Income inequality is a top-line concern of people and organizations all over the world, even some conservatives these days.

Reducing high-end consumption could have an enormous short-term impact on carbon emissions, as climate scientist Kevin Anderson is always saying. Shifting wealth within populations — reducing the number of very wealthy and the number in poverty — can have as much carbon impact as reducing overall population.

So maybe, at the next environmental event, you could ask the income inequality question rather than the population question.

Environmentalism as a political movement now has a nearly global reputation as a movement of rich white people telling other people what they are doing wrong while doing nothing to change their own consumption patterns or acting in solidarity with other movements. Some of this reputation is unjustified, but it has too much truth in it. Far too many environmentalists, and in this case they are nearly universally rich and white, want to talk about overpopulation as the problem. Yet that’s always about stopping the brown people from reproducing, a tale that smacks of eugenics. Meanwhile, it’s wealthy first world consumption driving climate change. That’s a far greater problem than people in Nigeria and Bangladesh having children. Moreover, as Roberts points out, there are ways to work to limit overpopulation and that’s empowering women to have control over their own bodies and lives. Sitting in our suburban homes complaining about those people having their babies while getting ready to load the Forrester for our hiking or climbing adventure in the mountains isn’t just absurd, it’s hypocritical and borderline racist.

Don’t be that environmentalist. Be the environmentalist who is pro-person and wants to help all living people live better lives that give them power to make their own choices while fighting for government actions that would mitigate climate change. It’s the political, ethical, and moral right way to position oneself. Wanting to close the borders to the world’s poor or bemoan their fertility is politically disastrous, morally bankrupt, and utterly unethical.